rim damage asymetric hop?

Hi all sorry to keep asking questions but I just got a NOS 2002 Iron
horse Victory and am working out all the kinks.

This question has to do with a rear wheel. I trued it up pretty well
but the rear one has a hop. It is strange because I thought a low spot
usually has a high spot on the other side of the wheel. In this case it has
one low spot ~1.5 mm. The rest of the rim is nearly perfect both radially
and laterally and dish. There is no detectable damage to the rim. The only
thing I could find is 2 creases beside one spoke hole on the V section of
the rim not the braking surface. It is light and barely noticeable and does
not actually touch the hole. My question is what could be causing it and
how should I fix it. Should I loosen the 3 spokes around it to bring the
rim out or will that simply mess us the other side of the rim as well?
The wheel is 32 spoke mavic cxp 11 and tiagra hub.

Steven S wrote:
Hi all sorry to keep asking questions but I just got a NOS 2002 Iron
horse Victory and am working out all the kinks.

This question has to do with a rear wheel. I trued it up pretty well
but the rear one has a hop. It is strange because I thought a low spot
usually has a high spot on the other side of the wheel.

no, the rim is too flexible for that. you usually get flat spots either
where spokes are too tight or where the rim's bent.

In this case it has
one low spot ~1.5 mm. The rest of the rim is nearly perfect both radially
and laterally and dish. There is no detectable damage to the rim. The only
thing I could find is 2 creases beside one spoke hole on the V section of
the rim not the braking surface. It is light and barely noticeable and does
not actually touch the hole. My question is what could be causing it and
how should I fix it. Should I loosen the 3 spokes around it to bring the
rim out or will that simply mess us the other side of the rim as well?
The wheel is 32 spoke mavic cxp 11 and tiagra hub.



check relative spoke tension first. assuming no gotchas like
inconsistent spoke gauge, if they're tighter at the flat spot, that's
your problem. if they're looser at the flat spot, the rim's bent.

if re-truing a modern dished rear wheel, it's a good first approximation
to assume radial roundness is controlled by drive side spokes and true
is by non-drive spokes.

On Jun 8, 9:34 pm, jim beam wrote:
if re-truing a modern dished rear wheel, it's a good first approximation
to assume radial roundness is controlled by drive side spokes and true
is by non-drive spokes.

It's true that for lateral truing there is about a 2 to 1 ratio in
favor of the NDS, but for radial they should be nearly equal in
effect. Of course, to maintain lateral true you will still need to
tighten or loosen the DS twice as much as the NDS... maybe that is
what you meant

Steven S... if the rim is badly bent, meaning it isn't round with even
spoke tension, then the only solution...except for replacing it... is
to try and bend it back into shape. If you have plenty of spare time
you can try loosening the spokes in the effected area and pull the rim
until it yields slightly. Then try tightening the spokes again and see
if you made it better. There used to be tools for this, but I don't
know if shops carry them anymore.

Ah so this is what a flat spot is. I never saw one before so I didn't know.
Upon plucking the spoke centered on it is a very slight amount looser than
its neightbors but not by too much. When it get time I'll remove the spokes
in the area and hit it with a mallet to try and get it back into shape.
Thanks for the help.

"Ron Ruff" wrote in message
ups.com...
On Jun 8, 9:34 pm, jim beam wrote:
if re-truing a modern dished rear wheel, it's a good first approximation
to assume radial roundness is controlled by drive side spokes and true
is by non-drive spokes.

It's true that for lateral truing there is about a 2 to 1 ratio in
favor of the NDS, but for radial they should be nearly equal in
effect. Of course, to maintain lateral true you will still need to
tighten or loosen the DS twice as much as the NDS... maybe that is
what you meant

Steven S... if the rim is badly bent, meaning it isn't round with even
spoke tension, then the only solution...except for replacing it... is
to try and bend it back into shape. If you have plenty of spare time
you can try loosening the spokes in the effected area and pull the rim
until it yields slightly. Then try tightening the spokes again and see
if you made it better. There used to be tools for this, but I don't
know if shops carry them anymore.

Steven S wrote:
Ah so this is what a flat spot is. I never saw one before so I didn't know.
Upon plucking the spoke centered on it is a very slight amount looser than
its neightbors but not by too much. When it get time I'll remove the spokes
in the area and hit it with a mallet to try and get it back into shape.

you can cause local denting doing that. you need a block between mallet
and rim to spread the blow area. ideally a sculpted block.


Thanks for the help.

"Ron Ruff" wrote in message
ups.com...
On Jun 8, 9:34 pm, jim beam wrote:
if re-truing a modern dished rear wheel, it's a good first approximation
to assume radial roundness is controlled by drive side spokes and true
is by non-drive spokes.
It's true that for lateral truing there is about a 2 to 1 ratio in
favor of the NDS, but for radial they should be nearly equal in
effect. Of course, to maintain lateral true you will still need to
tighten or loosen the DS twice as much as the NDS... maybe that is
what you meant

Steven S... if the rim is badly bent, meaning it isn't round with even
spoke tension, then the only solution...except for replacing it... is
to try and bend it back into shape. If you have plenty of spare time
you can try loosening the spokes in the effected area and pull the rim
until it yields slightly. Then try tightening the spokes again and see
if you made it better. There used to be tools for this, but I don't
know if shops carry them anymore.

On Jun 8, 10:01 pm, "Steven S" loach_lover[remove spam
wrote:
Hi all sorry to keep asking questions but I just got a NOS 2002 Iron
horse Victory and am working out all the kinks.

This question has to do with a rear wheel. I trued it up pretty well
but the rear one has a hop. It is strange because I thought a low spot
usually has a high spot on the other side of the wheel. In this case it has
one low spot ~1.5 mm. The rest of the rim is nearly perfect both radially
and laterally and dish. There is no detectable damage to the rim. The only
thing I could find is 2 creases beside one spoke hole on the V section of
the rim not the braking surface. It is light and barely noticeable and does
not actually touch the hole. My question is what could be causing it and
how should I fix it. Should I loosen the 3 spokes around it to bring the
rim out or will that simply mess us the other side of the rim as well?
The wheel is 32 spoke mavic cxp 11 and tiagra hub.

If you find some spokes tighter than the rest, sure, give it a whirl.
I'd likely just leave it if I couldn't feel it while riding and mess
with it on a rainy evening during the winter to alleviate boredom.

loosen the flat spot spokes plus one or two more both sides
then loosen the opposite side spokes about half as much
keeping track of where you are with tape on each spoke
start from the middle and work to the sides, counting
that will move the hub (and spokes it carries) toward the flat spot
while more or less passing the sides
XD